The principle underlying the function of odorant precursor compounds is fundamentally known. It generally involves converting odorants into compounds which do not bring about a direct scent or aroma impression but which, in response to a specific stimulus, for example on exposure to heat or acid, are capable of releasing the original odorant and thus obtain a scenting or aroma action. The intention here is to protect the odorant until it is released in targeted manner.
Known odorant precursors are for example silicic acid esters. Such compounds are described in German published patent application DE 198 41 147 A1. These silicic acid esters contain residues of scent alcohols, such as for example octan-1-ol, and are suitable for fragrancing washing and cleaning agents since they release the alcohols with a scenting action on hydrolysis.
Oxazolidine-based odorant precursors are furthermore known. Such compounds are described in German published patent application DE 10 2006 003 092 A1. The odorant precursors described therein are bicyclic oxazolidine derivatives of scent ketones or aldehydes, such as for example decanal, which are capable of releasing the aldehydes or ketones with a scenting action on hydrolysis.
Photolabile odorant precursors are also known, which enable photoinduced release of odorants. Such compounds are described in German published patent application DE 10 2008 016 327 A1. The systems described therein are specific ketones which enable the release of terpenoids or terpenes with a scenting action, such as for example β-phellandrene, after exposure to electromagnetic radiation including the wavelengths from 200 to 400 nm.
In J. Org. Chem. 1999, 64, 54-59, J. Wennerberg et al. describe catalysts for the retro-ene reaction-related rearrangement of benzyl allyl ethers. In J. Am. Chem. Soc, 1973, 95, 5234-5242, H. Kwart et al. describe the thermally induced reaction of allyl ethers. However, neither odorant compositions nor washing or cleaning agents are described therein.
Against this background, it was the object of the present invention to provide further compositions which enable targeted odorant release.
Said object is achieved by the subject matter of the invention, namely an odorant composition, containing an odorant precursor, which is an allyl ether of the formula (I),R1R2C═CR3—CR4R5—O—CHR6R7  (I),in which the residues R1, R2, R3, R4, R5, R6 and R7 mutually independently in each case denote H or a hydrocarbon residue that can be acyclic or cyclic, substituted or unsubstituted, branched or unbranched, as well as saturated or unsaturated, and in which individual residues R1, R2, R3, R4, R5, R6, R7 can form a ring system with one another, wherein R1, R2, R3, R4 and R5 denote residues that, in a compound of the general formula (II)R1R2CH—CR3═CR4R5  (II)give rise to an odorant, in which the residue R3 can form a ring system with one of residues R1 or R5,and/or wherein R6 and R7 denote residues that, in a compound of the general formula (III)R6R7C═O  (III)give rise to an odorant, in which residues R6 and R7 can preferably form a ring system. The respective hydrocarbon residues may advantageously in each case comprise 1 to preferably 15 carbon atoms.
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.